Add hook to provide GrpcInterceptorProvider Settings

modules/transport-grpc/spi/src/main/java/org/opensearch/transport/grpc/spi/GrpcInterceptorProvider.java

@@ -7,6 +7,7 @@
  */
 package org.opensearch.transport.grpc.spi;
 
+import org.opensearch.common.settings.Settings;
 import org.opensearch.common.util.concurrent.ThreadContext;
 
 import java.util.List;
@@ -20,6 +21,12 @@
  */
 public interface GrpcInterceptorProvider {
 
+    /**
+     * Provide visibility into node settings.
+     * @param settings for use in interceptors.
+     */
+    default void initNodeSettings(Settings settings) {}
+
     /**
      * Returns a list of ordered gRPC interceptors with access to ThreadContext.
      * Each interceptor must have a unique order value.

modules/transport-grpc/src/main/java/org/opensearch/transport/grpc/GrpcPlugin.java

@@ -349,6 +349,7 @@ public Collection<Object> createComponents(
         // Then add plugin-provided interceptors
         if (!interceptorProviders.isEmpty()) {
             for (GrpcInterceptorProvider provider : interceptorProviders) {
+                provider.initNodeSettings(environment.settings());
                 orderedList.addAll(provider.getOrderedGrpcInterceptors(threadPool.getThreadContext()));
             }
 

modules/transport-grpc/src/test/java/org/opensearch/transport/grpc/GrpcPluginTests.java

@@ -14,6 +14,7 @@
 import org.opensearch.common.settings.Settings;
 import org.opensearch.common.util.concurrent.ThreadContext;
 import org.opensearch.core.indices.breaker.CircuitBreakerService;
+import org.opensearch.env.Environment;
 import org.opensearch.plugins.ExtensiblePlugin;
 import org.opensearch.plugins.SecureAuxTransportSettingsProvider;
 import org.opensearch.protobufs.QueryContainer;
@@ -83,6 +84,9 @@ public class GrpcPluginTests extends OpenSearchTestCase {
     @Mock
     private Client client;
 
+    @Mock
+    private Environment environment;
+
     private NetworkService networkService;
 
     private ClusterSettings clusterSettings;
@@ -102,8 +106,9 @@ public void setup() {
         // Create a real ClusterSettings instance with the plugin's settings
         plugin = new GrpcPlugin();
 
-        // Mock ThreadPool and ThreadContext
+        // Mock ThreadPool/ThreadContext/Environment
         when(threadPool.getThreadContext()).thenReturn(new ThreadContext(Settings.EMPTY));
+        when(environment.settings()).thenReturn(Settings.EMPTY);
 
         // Set the client in the plugin
         plugin.createComponents(
@@ -113,7 +118,7 @@ public void setup() {
             null, // ResourceWatcherService
             null, // ScriptService
             null, // NamedXContentRegistry
-            null, // Environment
+            environment, // Environment
             null, // NodeEnvironment
             null, // NamedWriteableRegistry
             null, // IndexNameExpressionResolver
@@ -448,12 +453,11 @@ public void testLoadExtensionsWithDuplicateGrpcInterceptorOrder() {
 
         IllegalArgumentException exception = expectThrows(
             IllegalArgumentException.class,
-            () -> plugin.createComponents(client, null, mockThreadPool, null, null, null, null, null, null, null, null)
+            () -> plugin.createComponents(client, null, mockThreadPool, null, null, null, environment, null, null, null, null)
         );
 
         String errorMessage = exception.getMessage();
         assertTrue(errorMessage.contains("Multiple gRPC interceptors have the same order value [1]"));
-        assertTrue(errorMessage.contains("ServerInterceptor")); // Mock class name will contain this
         assertTrue(errorMessage.contains("Each interceptor must have a unique order value"));
     }
 
@@ -470,12 +474,11 @@ public void testLoadExtensionsWithMultipleProvidersAndDuplicateOrder() {
 
         IllegalArgumentException exception = expectThrows(
             IllegalArgumentException.class,
-            () -> plugin.createComponents(client, null, mockThreadPool, null, null, null, null, null, null, null, null)
+            () -> plugin.createComponents(client, null, mockThreadPool, null, null, null, environment, null, null, null, null)
         );
 
         String errorMessage = exception.getMessage();
         assertTrue(errorMessage.contains("Multiple gRPC interceptors have the same order value [5]"));
-        assertTrue(errorMessage.contains("ServerInterceptor"));
         assertTrue(errorMessage.contains("Each interceptor must have a unique order value"));
     }
 
@@ -498,12 +501,11 @@ public void testLoadExtensionsWithSameExplicitOrderInterceptors() {
 
         IllegalArgumentException exception = expectThrows(
             IllegalArgumentException.class,
-            () -> plugin.createComponents(client, null, mockThreadPool, null, null, null, null, null, null, null, null)
+            () -> plugin.createComponents(client, null, mockThreadPool, null, null, null, environment, null, null, null, null)
         );
 
         String errorMessage = exception.getMessage();
         assertTrue(errorMessage.contains("Multiple gRPC interceptors have the same order value [5]"));
-        assertTrue(errorMessage.contains("ServerInterceptor"));
         assertTrue(errorMessage.contains("Each interceptor must have a unique order value"));
     }
 
@@ -742,13 +744,31 @@ private void testRequestProcessingWithException(
     }
 
     /**
-     * Creates a mock interceptor with given order
+     * Creates a no-op interceptor with the specified order.
      */
     private OrderedGrpcInterceptor createMockInterceptor(int order) {
-        OrderedGrpcInterceptor mock = Mockito.mock(OrderedGrpcInterceptor.class);
-        when(mock.order()).thenReturn(order);
-        when(mock.getInterceptor()).thenReturn(Mockito.mock(ServerInterceptor.class));
-        return mock;
+        return new OrderedGrpcInterceptor() {
+
+            @Override
+            public int order() {
+                return order;
+            }
+
+            @Override
+            public ServerInterceptor getInterceptor() {
+                return new ServerInterceptor() {
+                    @Override
+                    public <ReqT, RespT> ServerCall.Listener<ReqT> interceptCall(
+                        ServerCall<ReqT, RespT> call,
+                        Metadata headers,
+                        ServerCallHandler<ReqT, RespT> next
+                    ) {
+                        // no-op interceptor
+                        return next.startCall(call, headers);
+                    }
+                };
+            }
+        };
     }
 
     private void assertDoesNotThrow(Runnable runnable) {
@@ -901,7 +921,9 @@ public void testGrpcInterceptorChainIntegrationWithPlugin() {
         ThreadPool mockThreadPool = Mockito.mock(ThreadPool.class);
         when(mockThreadPool.getThreadContext()).thenReturn(new org.opensearch.common.util.concurrent.ThreadContext(Settings.EMPTY));
 
-        assertDoesNotThrow(() -> plugin.createComponents(client, null, mockThreadPool, null, null, null, null, null, null, null, null));
+        assertDoesNotThrow(
+            () -> plugin.createComponents(client, null, mockThreadPool, null, null, null, environment, null, null, null, null)
+        );
     }
 
     public void testGrpcInterceptorChainWithDuplicateOrders() {
@@ -929,7 +951,7 @@ public void testGrpcInterceptorChainWithDuplicateOrders() {
         // Should throw exception due to duplicate orders during createComponents
         IllegalArgumentException exception = expectThrows(
             IllegalArgumentException.class,
-            () -> plugin.createComponents(client, null, mockThreadPool, null, null, null, null, null, null, null, null)
+            () -> plugin.createComponents(client, null, mockThreadPool, null, null, null, environment, null, null, null, null)
         );
 
         // Verify error message includes order value and interceptor class names
@@ -984,6 +1006,55 @@ private void testGrpcInterceptorChain(List<OrderedGrpcInterceptor> interceptors,
         }
     }
 
+    public void testGrpcInterceptorProviderSettingsInitialization() {
+        // Mock extension loading for GrpcPlugin
+        TestSettingsAwareInterceptorProvider provider = new TestSettingsAwareInterceptorProvider();
+        ExtensiblePlugin.ExtensionLoader mockLoader = Mockito.mock(ExtensiblePlugin.ExtensionLoader.class);
+        when(mockLoader.loadExtensions(QueryBuilderProtoConverter.class)).thenReturn(null);
+        when(mockLoader.loadExtensions(GrpcInterceptorProvider.class)).thenReturn(List.of(provider));
+        GrpcPlugin plugin = new GrpcPlugin();
+        plugin.loadExtensions(mockLoader);
+
+        // Mock Environments
+        Settings validSetting = Settings.builder().put("test-setting", true).build();
+        Environment validEnv = Mockito.mock(Environment.class);
+        when(validEnv.settings()).thenReturn(validSetting);
+
+        Settings invalidSetting = Settings.builder().put("test-setting", false).build();
+        Environment invalidEnv = Mockito.mock(Environment.class);
+        when(invalidEnv.settings()).thenReturn(invalidSetting);
+
+        Settings emptySetting = Settings.builder().build();
+        Environment emptyEnv = Mockito.mock(Environment.class);
+        when(emptyEnv.settings()).thenReturn(emptySetting);
+
+        // createComponents initializes interceptor with the correct setting
+        assertDoesNotThrow(() -> plugin.createComponents(client, null, threadPool, null, null, null, validEnv, null, null, null, null));
+
+        // createComponents throws exception with the incorrect setting
+        try {
+            plugin.createComponents(client, null, threadPool, null, null, null, invalidEnv, null, null, null, null);
+            fail("Expect test interceptor with wrong settings throws exception.");
+        } catch (RuntimeException e) {
+            assertEquals("test-setting not found or not set to true", e.getMessage());
+        }
+
+        // createComponents throws exception with empty setting
+        try {
+            plugin.createComponents(client, null, threadPool, null, null, null, emptyEnv, null, null, null, null);
+            fail("Expect test interceptor with empty settings throws exception.");
+        } catch (RuntimeException e) {
+            assertEquals("test-setting not found or not set to true", e.getMessage());
+        }
+    }
+
+    public void testGrpcInterceptorProviderEmpty() {
+        GrpcInterceptorProvider prov = threadContext -> List.of();
+        assertDoesNotThrow(() -> prov.initNodeSettings(Settings.EMPTY));
+        List<OrderedGrpcInterceptor> interceptors = prov.getOrderedGrpcInterceptors(new ThreadContext(Settings.EMPTY));
+        assertTrue(interceptors.isEmpty());
+    }
+
     /**
      * Creates a test interceptor that can succeed or fail
      */
@@ -1040,4 +1111,45 @@ public <ReqT, RespT> ServerCall.Listener<ReqT> interceptCall(
         };
     }
 
+    /**
+     * Test interceptor provider that validates GrpcInterceptorProvider's access to settings.
+     * TestSettingsAwareInterceptorProvider will throw an exception if setting "test-setting" is not true.
+     */
+    private static class TestSettingsAwareInterceptorProvider implements GrpcInterceptorProvider {
+        private Settings settings;
+
+        @Override
+        public void initNodeSettings(Settings settings) {
+            this.settings = settings;
+        }
+
+        @Override
+        public List<OrderedGrpcInterceptor> getOrderedGrpcInterceptors(ThreadContext threadContext) {
+            if (settings == null || !settings.getAsBoolean("test-setting", false)) {
+                throw new RuntimeException("test-setting not found or not set to true");
+            }
+
+            return List.of(new OrderedGrpcInterceptor() {
+                @Override
+                public int order() {
+                    return 100;
+                }
+
+                @Override
+                public ServerInterceptor getInterceptor() {
+                    return new ServerInterceptor() {
+                        @Override
+                        public <ReqT, RespT> ServerCall.Listener<ReqT> interceptCall(
+                            ServerCall<ReqT, RespT> call,
+                            Metadata headers,
+                            ServerCallHandler<ReqT, RespT> next
+                        ) {
+                            // No-op interceptor - just pass through
+                            return next.startCall(call, headers);
+                        }
+                    };
+                }
+            });
+        }
+    }
 }